When insulation caps are molded from synthetic resin materials by an injection molding machine, since injection molds have to be changed for materials and sizes of insulation caps to be molded, this approach using the injection molding machine is not suitable for multi-kind, small-lot production. Then, the applicant of the present patent application proposed an insulation cap manufacturing apparatus described in PTL 1.
The insulation cap manufacturing apparatus 100 includes, as is shown in FIG. 10, first to third tube feeding units 102, 103, 104 which are disposed on a base 101 at intervals in a tube transport direction ‘A’, a tube welding unit 105 disposed directly downstream of the first tube feeding unit 102 on the base 101, and a cap blanking unit 106 disposed between the second and third tube feeding units 103, 104 on the base 101.
The first to third tube feeding units 102, 103, 104 have pairs of upper and lower rollers 102a, 102b, 103a, 103b, 104a, 104b, respectively, and a long tube 110 is disposed between the pairs of upper and lower rollers 102a, 102b, 103a, 103b, 104a, 104b. The long tube 110 is transported by a specified amount every time the pairs of upper and lower rollers 102a, 102b, 103a, 103b, 104a, 104b are rotated.
The tube welding unit 105 has a pair of upper and lower welding portions 105a, 105b and performs a welding operation on the tube 110 held by the rollers.
The tube blanking unit 106 has a lower receiving table 106a, an upper blanking portion 106b and a cutting portion 106c. The tube blanking unit 106 blanks an insulation cap 109 (shown in FIG. 11) out of the tube 110.
Next, the operation of the manufacturing apparatus 100 will be described. When the long tube 110 is fed out by a specified amount by the first to third tube feeding units 102, 103, 104, the transport of the tube 110 is stopped in a specified position. Next, in the tube welding unit 105, the upper welding portion 105a is lowered to a position where the upper welding portions 105a is brought into press contact with the lower welding portion 105b, so as to perform a welding operation on the tube 110.
In the tube blanking unit 106, the upper blanking portion 106b and the cutting portion 106c are lowered towards the lower receiving table 106a at the same time as the welding operation is performed on the tube 110, so as to perform a blanking operation on the tube 110. As is shown in FIG. 11, two insulation caps 109 are produced through a single blanking step.
When the tube welding operation and the insulation cap blanking operation are completed, the manufacturing flow proceeds to the tube feeding step by the tube feeding units 102, 103, 104. Insulation caps 109 are manufactured continuously by repeating sequentially the operations.